Recurrent and Second Primary Squamous Cell Carcinoma of the Oral Cavity in the Previously Irradiated Territory in Case of Primary Unresectable Tumor.; Recurrent and Second Primary Squamous Cell Carcinoma of the Oropharynx in the Previously Irradiated Territory in Case of Primary Unresectable Tumor.; Recurrent and Second Primary Squamous Cell Carcinoma of the Hypopharynx in the Previously Irradiated Territory in Case of Primary Unresectable Tumor.; Recurrent and Second Primary Squamous Cell Carcinoma of the Larynx in the Previously Irradiated Territory in Case of Primary Unresectable Tumor.